Fix dnf error by removing localpkg_only and improve repo search

iridium_installer/backend/os_install.py

@@ -137,6 +137,7 @@ def install_minimal_os(mount_root, releasever="43"):
         "/run/install/source",
         "/mnt/install/repo",
         "/run/initramfs/live",
+        "/run/initramfs/isoscan",
     ]
     
     iso_repo = None
@@ -156,11 +157,12 @@ def install_minimal_os(mount_root, releasever="43"):
             f"--repofrompath=iridium-iso,{iso_repo}",
             "--enablerepo=iridium-iso",
             "--offline",
+            "--cacheonly",
         ]
     else:
         logger.warning("ISO repository not found in common locations. DNF might try to use network.")
         # Try to at least prevent some network usage
-        dnf_args = ["--setopt=localpkg_only=1", "--offline"]
+        dnf_args = ["--offline"]
 
     cmd = [
         "dnf",